Dial combination for radio receiving sets



March 10, 1942. J. PIERREL 2,275,463

DIAL COMBINATION FOR RADIO RECEIVING SETS Filed Feb. 6, 1939 2 Sheets-Sheet l March 10, 1942. J. PIERREL DIAL COMBINATION FOR RADIO RECEIVING SETS Filed Feb. 6, 1939 2 Sheets-Sheet 2 Patented Mar. 10, 1942 DIAL COMBINATION FOR. RADIO RECEIVING SETS Joseph Pierre], New York, N. Application February 6, 1939, Serial No. 254,907

7 Claims.

This invention relates to indicating dials used in connection with radio receivers.

The object of my invention is to provide a radio dial that will render it easier for the general public to tune in short wave transmitters generally and in particular the stations on the international broadcast bands.

Radio dials of the present art featuring the short wave frequency range are commonly deficient by not showing the station designations of the short wave transmitters or showing only a relatively small number of them, and by not providing an amount of calibration spread sufiicient for convenient tuning and for. placing the station designations against the calibration scales.

One preferred embodiment of my invention combines on the dial chart, not too large for being acceptable to the general public, of a radio receiver, the following features.

(a) The complete scale of the present short wave range from about 55 meters, to about 10 meters;

' (b) Suificient bandspread in particular for the transmitter groupings now commonly known as international broadcast bands so that the listener may be able to log a station more conveniently;

Room for substantially all of the station designations of said international broadcast bands, that is to say at present of about four hundred transmitters;

(d) Simplicity of manufacture and operation, one single pointer sweeping over one single dial chart.

Those features seem to be exclusive of each 35 other, but are not so by the use of my invention. Still other features are provided which will be apparent to those skilled in the art.

The means by which I realize the objects of my invention embodies a combination of staggering and displacement arrangements as described in this specification and illustrated in the drawings accompanying the specification.

In the drawings chosen for illustrating my invention, Figs. 1 and 1a represent the spread-out surface of a conical dial chart moving against a fixed pointer bar (not shown). The dial chart represents that of an all wave receiver tuning in transmissions from about 100 kilocycles to about 24,000 kilocycles.

The Roman numerals I to VIII designate the eight wave bands of an all wave receiver.

The scale designated by IX is an all purpose precision tuning scale.

The arcuatespaces designated by X, XI, XII

and XIII are designed to receive station designations as commonly practiced in the art up to now.

The large space XIV is additional space designed to make possible the large groups of station designations found in certain transmitter groupings and especially in the international broadcast bands.

Beginning at the lower left hand corner of the drawing (Fig. 1) there is the group of station designations marked by the letter A. These are a number of stations of the 180 meter police band.

In the following two spaces B and C may be placed station designations of amateur transmitters.

These three groups of station designations A, B and C are immediately adjacent to their relevant calibration scale and no special displacement arrangement is necessary to show them, provided only that they are staggered in relation to other groups, that is to say, that no other large groups of station designations happen to fall in that place.

Group D is a bandspread projection out of scale VII, that is to say, the amateur phone band from 14,150 to 14,250 kc. has been duplicated here on a larger radius and consequently more calibration spread and space is available for station designations.

Group E represents, for tropical and subtropical zones, the 160 meter broadcast band. Group F represents for the United States, the 160 meter police band. The two bands E and F are of the same character as the bands A, B and C.

Group G represents the 49 meter international broadcast band. The station designations are shown as written directly against the main calibration scale, as this scale has suflicient calibration spread. Space is provided for the numerous station designations by shifting that part of scale V which was opposite, outwardly.

Group H is a bandspread projection, into the additional space, out of scale VII, providing for the 19 meter international broadcast band additional bandspread and room for station designations.

Space I is designed to receive the station designations of the meter tropical and subtropical broadcast band in a way similar to groups A, B, C, E and F.

Group J is a calibration spread projection out of scale VI and represents the 25 meter international broadcast band.

Group K is a calibration spreadprojection out prior art.

of scale VIII and represents the 13 meter international broadcast band.

Space L can receive, directly adjacent to the calibration scaleIII, the station designations of the 60 meter tropical and subtropical broadcast band.

Group M represents the 31 meter international broadcast band. Room is made for those station designations by shifting their own calibration scale outwards, thus providing also additional bandspread for these stations.

Group N represents the 40 meter international broadcast band directly adjacent to its scale which has sufficient bandspread. Opposite it the shifting, out of place, of scale V is continued.

Group is the bandspread projection, out of scale VIII, of the 16 meter international broadcast band.

To appreciate the advantages of my invention, there may be considered the difficulties of the If in order to feature the station designations of the international broadcast bands, the arcuate spaces X, XI, XII and E11 had been made to contain within themselves the groups of station designations of the various transmitter groupings projected, or continued, into the additional space XIV, all those spaces would have had to be on the average about four times as wide as they actually are, thus greatly increasing the size of the dial chart. At the same time those transmitter groupings, although causing a widening of said arcuate spaces X to XIII all along their length, would actually have occupied only an extremely small part of them, leaving most of the rest empty.

If all the scales had been provided throughout with a calibration spread sufficient to place against the calibrations the names of the station designations of the international broadcast bands,'giving each kilocycle span a calibration interval of 2 millimeters, there would have had to be accommodated on the dial, chart a scale 48 meters long.

The projections and shiftings effected'as shown on the drawings permit giving at the same time the continuous scale of the short wave range and the necessary calibration spread for those parts of it in which the average listener is mostly interested, together with all the station designations, on a dial of acceptable proportions.

It can be seen that these displacement ar-, rangements require the staggering ofthe transmitter groupings in question, and this staggering is obtained through an appropriate combination of wave bands. erable number of suitable wave band arrangements are possible.

In the arrangement represented in the draw-' ings, the capacity of the tuning condenser is assumed to be identical for the five short wave bands IV to VIII. The capacity for the two bands II and III is likewise identical but it obviously is of greater. value than that used.on bands IV to VIII. Band I would be tuned with a. still higher capacity.

In spite of the tuning capacity being the same for bands II and III, calibration for band III: is about the same as that of band II owing to the fact that band II is represented on a small scale near the apex of the cone whereas band III is spread out over a large scale near the bottom of the cone. Bands IV and V have a far greater calibration spread than bands VI VII and VIII, not only forrepresenting lower frequencies, but

It is also obvious that a considr also for the fact that their scales are placed on a greater radius than the bands representing higher frequencies. The, reason for this arrangement is that there are found in band V and especially in band IV a great many broadcast stations distributed all over the band, outside of the international broadcast bands properly speaking; whereas bands VI, VII and VIII have practically no stations of public interest outside of the international broadcast bands which can be satisfactorily logged in their bandspread projections.

In the case of the fixed dial with rotating pointer it is desirable to locate the desired transmitter groupings along the ascending and descending sections of the circular scales so as to be .able to place the station designations against the scales horizontally, or nearly so, for more convenient reading on the part of the listener.

Since transmitting stations change their frequencies, and since new transmitters come in and some old ones drop out, it is advisable to make the dial chart exchangeable by any suitable arrangement known in the art. Such printed replacement dials could be furnished to the listeners about three or four times a year by an agency equipped for rendering that service.

Considered from the standpoint of transmitter groupings distributed over only two wave bands, the station designations of the staggered transmitter groupings may simply be placed between the two calibration scales, the staggered relation of 'thegroups of station designations reducing the width of the intermediary space necessary for the station designations.

The advantage derived, however, from this elementary combination is relatively small. To some extent itis represented in the drawings where the police band (II) with the immediately adjacent groups A, B, C, E, F, I and L would represent one-half, or one side, of such simple two-sided combination.

It is for the reason of the limited usefulness of this simple combination that the second means, the dial chart, is made to embody, in addition to thestaggering idea, the idea of displacing, in the direction of the pointer, groups of station designations, or sections of the calibration scales, or both, and generally of any tuning indicia given on the dial chart.

This displacement can take place under two forms, projection and shifting, both of which are illustrated in the drawings. In projection we have a break of continuity betweenthe projected part and the main scale out of which it was projected, with other scales in between them. In shifting there are no foreign elements between the shifted part and'those tuning indicia opposite away from which it was shifted.

The two ideas embodied in my invention, staggering and displacement, are complementary to each other. The idea of displacement alone would be of no use, for without preliminary staggering, displacements could not result in the saving of space which makes possible the showing of the large groups of station designations on av dial of acceptable size. On the other hand, if the staggering idea can be embodied in a simple realization of'the invention without the idea of displacement, the full benefit of staggering transmitter groupings is attained only through the complementary effect of the displacement to, but include all the various embodiments to which the principles here disclosed may apply.

I claim:

1. In combination with a radio receiver having means to tune it over a pair of wave bands, each of said bands having a plurality of nonadjacent portions assigned to predetermined transmitter groupings; spaced indication scales for said .bands and a pointer simultaneously cooperating with said scales, each scale having non-adjacent sections corresponding to said transmitter groupings, all the sections on onescale being staggered with respect to all the sections on the other scale.

2. Apparatus according to claim ,1, wherein the space between said scales bears station designations for all said transmitter groupings.

3. In a multiband radio receiver having continuously variable means for tuning over a group of wave bands, there being in said Wave bands a plurality of predetermined transmitter groupings and said transmitter groupings being distributed over at least two of said wave bands and being arranged in staggered relation to each other, the frequency range of the Wave bands containing predetermined staggered transmitter groupings being determined by the requirements of said staggering, a group of wave band scales and a pointer bar cooperating with one another and With said tuning means, said transmitter groupings being represented on nonoverlapping sections along the length of said group of scales and tuning indicia in at least one section of at least one wave band scale displaced in the direction of said pointer bar, said combined staggering and displacement reducing the amount of space required for the numerous station designations of said transmitter groupings and making possible the showing of a continuous scale of short wave frequencies, accompanied by substantially all the station designations of said transmitter groupings, with an appreciable amount of calibration spread, on a dial of acceptable proportions.

4. In a multiband radio receiver having continuously variable tuning means staggering predetermined transmitter groupings distributed over two wave hands, a group'of two calibration scales, a pointer cooperating with said scales, both said scales and said pointer cooperating with said tuning means, said two calibration scales representing said staggering of said transmitter groupings, space being providedbetween the two calibration scales for station designations, the staggered arrangement of the said transmitter groupings reducing the width of the space necessary for the station designations.

5. In a multiband radio receiver having continuously variable means to tune it over a group of wave bands, there being in said wave bands a plurality of predetermined transmitter groupings and said transmitter groupings being distributed over at least two of said wave bands and being arranged in staggered relation to each other, a group of wave band scales and a pointer cooperating with each other and cooperating with said tuning means, said transmitter fit groupings being represented on non-overlapping sections along the length of said group of scales, space being provided along the scales for station designations, and additional space being provided for the numerous station designations of said transmitter groupings, said transmitter groupings being projected, along the direction of the pointer, into said additional space and there grouped in staggered relation, thereby reducing the amount of space neededfor providing, in the course of a continuous scale of short wave frequencies, substantially all the station designations of said transmitter groupings, with an appreciable amount of calibration spread, on a single dial of acceptable size.

6. In a multiband radio receiver having a continuously variable means to tune it over a group of wave bands, there being in said wave bands a plurality of predetermined transmitter groupings and said transmitter groupings being distributed over at least two of said wave bands and being arranged in staggered relation to each other, a group of wave band scales and a pointer cooperating with each other and cooperating with said tuning means, the said transmitter groupings being represented on non-overlapping sections along the length or said group of scales, space being provided along the scales for station designations, sections of scales being shifted out of place, adjacent to the groups of station designations of said nonoverlapping sections representing predetermined transmitter groupings,

along the direction of the pointer bar, thereby in turn enlarging the spaces destined to receive the station designations and making room for the numerous station designations of said transmitter groupings with a minimum amount of lost space, so as to provide a continuous scale of short wave frequencies accompanied by substantially all the station designations of said transmitter groupings, with an appreciable amount of calibration spread, on a dial of acceptable size.

7. In a rnultiband radio receiver having a continuously variable tuning means staggering predetermined transmitter groupings distributed over at least two wave hands, a group of calibration scales and a pointer cooperating with each other in relative rotational movement and cooperating with said tuning means, said group of calibration scales representing said staggering of said predetermined transmitter groupings, space being provided along the scales for station designations, and additional space being provided at a distance from the center of rotation greater than that of the main group of calibration scales, said transmitter groupings being projected, along the direction of the pointer, into said additional space, thereby reducing the amount of space needed for providing in the course of a continuous scale of short wavefroquencies, substantially all of the station designations of said transmitter groupings and for obtaining additional bandspread calibration for said transmitter groupings, on a dial of acceptable size.

JOSEPH PIERREL. 

